Filters








66 Hits in 2.9 sec

Separating IND-CPA and Circular Security for Unbounded Length Key Cycles [chapter]

Rishab Goyal, Venkata Koppula, Brent Waters
2017 Lecture Notes in Computer Science  
One interesting question is whether circular security comes for free from IND-CPA security.  ...  Given any fixed integer n, Koppula, Ramchen and Waters showed how to construct an IND-CPA scheme that is not n-circular secure using indistinguishability obfuscation (iO).  ...  However, an important related question is whether any IND-CPA scheme is also circular secure.  ... 
doi:10.1007/978-3-662-54365-8_10 fatcat:wd3fmijg2zb2bezgohpenhoswq

Indistinguishability Obfuscation from Circular Security [article]

Romain Gay, Rafael Pass
2020 IACR Cryptology ePrint Archive  
We show the existence of indistinguishability obfuscators (iO) for general circuits assuming subexponential security of: (a) the Learning with Error (LWE) assumption (with subexponential modulus-to-noise  ...  The circular security conjecture states that a notion of leakage-resilient security, that we prove is satisfied by GSW assuming LWE, is retained in the presence of an encrypted key-cycle involving GSW  ...  between circular SRL-security and "plain" circular security.  ... 
dblp:journals/iacr/GayP20 fatcat:a4diwwuwofbx5g4gmr43ffzkym

Lockable Obfuscation

Rishab Goyal, Venkata Koppula, Brent Waters
2017 2017 IEEE 58th Annual Symposium on Foundations of Computer Science (FOCS)  
This results in new separation results from learning with error including a public key bit encryption scheme that it IND-CPA secure and not circular secure.  ...  We first show how to create new separation results in circular encryption that were previously based on indistinguishability obfuscation.  ...  . √ q · I n || 0 n×(m−n) Figure 3 : 3 n-Cycle Tester 6.1 Separating IND-CPA Security from n-Circular Security Game 1 : 1 This game is the original IND-CPA security game described in Definition 2.4.  ... 
doi:10.1109/focs.2017.62 dblp:conf/focs/GoyalKW17 fatcat:vbaadqt3ofarpaynqwxhot5voe

Circular Security Separations for Arbitrary Length Cycles from LWE [chapter]

Venkata Koppula, Brent Waters
2016 Lecture Notes in Computer Science  
sized circuits), for any k there exists schemes that are IND-CPA secure, but that are not k-circular secure.  ...  One interesting question is whether k-circular security can come "for free". Is there some k such that any IND-CPA secure encryption scheme is guaranteed to be k-circular secure?  ...  obtaining separation between circular security and IND-CPA security.  ... 
doi:10.1007/978-3-662-53008-5_24 fatcat:whjakmqagvcr5j2smv6hbcgq6i

Indistinguishability Obfuscation versus Multi-bit Point Obfuscation with Auxiliary Input [chapter]

Christina Brzuska, Arno Mittelbach
2014 Lecture Notes in Computer Science  
While indistinguishability obfuscation is a general purpose obfuscation scheme, several obfuscators for specific functionalities have been considered.  ...  point functions with auxiliary input (MB-AIPO) have been constructed from composable AIPO by Canetti and Dakdouk (Eurocrypt 2008) and have been used by Matsuda and Hanaoka (TCC 2014) to construct CCA-secure  ...  [KRW13] show that if indistinguishability obfuscation exists, then IND-CPA-security of an encryption scheme does not imply its circular security, even if the cycles are of arbitrary polynomial-length.  ... 
doi:10.1007/978-3-662-45608-8_8 fatcat:b6u6guuiz5f5zarmxgs2fvhqdu

Obfuscation of Probabilistic Circuits and Applications [chapter]

Ran Canetti, Huijia Lin, Stefano Tessaro, Vinod Vaikuntanathan
2015 Lecture Notes in Computer Science  
We define several variants of pIO, using different approaches to formalizing the above security requirement, and study non-trivial relations among them.  ...  For obfuscation, we propose a notion that extends indistinguishability obfuscation to probabilistic circuits: It should be hard to distinguish between the obfuscations of any two circuits whose output  ...  and OWFs (without assuming circular security).  ... 
doi:10.1007/978-3-662-46497-7_19 fatcat:rtwezdv5bbavbc2hru7psjy26a

New Circular Security Counterexamples from Decision Linear and Learning with Errors [chapter]

Allison Bishop, Susan Hohenberger, Brent Waters
2015 Lecture Notes in Computer Science  
We have a particular interest in what qualities a cryptosystem must have to be able to separate such circular security from IND-CPA or IND-CCA security.  ...  Yet, if the function f is one way and the original system is IND-CPA secure, the resulting system will still be IND-CPA secure.  ...  We have a particular interest in what qualities a cryptosystem must have to be able to separate circular security from IND-CPA and IND-CCA security.  ... 
doi:10.1007/978-3-662-48800-3_32 fatcat:4pes6tcrxjactn6vjusfp3repe

On the Relationship between Functional Encryption, Obfuscation, and Fully Homomorphic Encryption [chapter]

Joël Alwen, Manuel Barbosa, Pooya Farshim, Rosario Gennaro, S. Dov Gordon, Stefano Tessaro, David A. Wilson
2013 Lecture Notes in Computer Science  
We conclude the paper by recasting the construction of RFE schemes in the context of obfuscation.  ...  For this we define the notion of entropically secure FE and use it as an intermediary step in the construction.  ...  The following implications are easy to verify: IND-CPA =⇒ R-IND-CPA ; R-IND-CPA + MH =⇒ IND-CPA . Fig. 5 : 5 Game defining the IND-ECPA security of an FE scheme.  ... 
doi:10.1007/978-3-642-45239-0_5 fatcat:gml6vajgqjhevgm6ydofrok6pi

Candidate Obfuscation via Oblivious LWE Sampling [article]

Hoeteck Wee, Daniel Wichs
2020 IACR Cryptology ePrint Archive  
We present a new, simple candidate construction of indistinguishability obfuscation (iO).  ...  Instead, we formulate a new falsifiable assumption under which the scheme is secure. Furthermore, the scheme plausibly achieves post-quantum security.  ...  of 0, and the latter clearly cannot harm IND-CPA security.  ... 
dblp:journals/iacr/WeeW20 fatcat:aiwgrakt75gzvdwggvchkbod2y

Obfuscating Finite Automata [article]

Steven D. Galbraith, Lukas Zobernig
2020 IACR Cryptology ePrint Archive  
In particular, the possibility of evaluating regular expressions solves the open problem of obfuscated substring matching.  ...  Using obfuscated deterministic finite automata we can for example evaluate secret regular expressions or disjunctive normal forms on public inputs.  ...  Note that Definition 4.1 is closely related to the definition of IND-CPA security for an asymmetric cipher: The adversary is given a number of encryptions of known messages and needs to distinguish them  ... 
dblp:journals/iacr/GalbraithZ20 fatcat:xhsa2y4dzfg6tav5i3rm6puboe

Separating Semantic and Circular Security for Symmetric-Key Bit Encryption from the Learning with Errors Assumption [chapter]

Rishab Goyal, Venkata Koppula, Brent Waters
2017 Lecture Notes in Computer Science  
In this work we separate private-key semantic security from 1-circular security for bit encryption using the Learning with Error assumption.  ...  Prior works used the less standard assumptions of multilinear maps or indistinguishability obfuscation. To achieve our results we develop new techniques for obliviously evaluating branching programs.  ...  In particular, we show generically how to combine a IND-CPA secure, but not circular secure bit encryption with multi-bit CCA secure encryption to achieve a single bit encryption system that is IND-CPA  ... 
doi:10.1007/978-3-319-56614-6_18 fatcat:5qgt77uqnngpzigtoomjr3o4by

On Extractability Obfuscation [chapter]

Elette Boyle, Kai-Min Chung, Rafael Pass
2014 Lecture Notes in Computer Science  
(adaptive-message) indistinguishability-secure functional encryption for an unbounded number of key queries and unbounded message spaces.  ...  Namely, we refer to an extractability (or indistinguishability) obfuscator as succinct if it can be used to obfuscate (non-uniform) Turing machines, while ensuring that the size of the obfuscated code  ...  Assuming the FHE scheme E is IND-CPA secure, then the outputs of Hyb 0 and Hyb 1 are computationally indistinguishable. Claim 3. 10 ( 10 Security of FHE).  ... 
doi:10.1007/978-3-642-54242-8_3 fatcat:3khqmnbqjbcw5jqiwbflbd62ui

On Strong Simulation and Composable Point Obfuscation

Nir Bitansky, Ran Canetti
2013 Journal of Cryptology  
The Virtual Black Box (VBB) property for program obfuscators provides a strong guarantee: Anything computable by an efficient adversary given the obfuscated program can also be computed by an efficient  ...  However, no composable VBB-obfuscators for point programs have been shown.  ...  VBB, IND and BP Obfuscation We first recall the virtual black box definition and two of its previous relaxations. Definition 2.1 (obfuscator [3] ).  ... 
doi:10.1007/s00145-013-9146-9 fatcat:blmu5whfmnfcnkyluagyqixt7a

On Strong Simulation and Composable Point Obfuscation [chapter]

Nir Bitansky, Ran Canetti
2010 Lecture Notes in Computer Science  
The Virtual Black Box (VBB) property for program obfuscators provides a strong guarantee: Anything computable by an efficient adversary given the obfuscated program can also be computed by an efficient  ...  However, no composable VBB-obfuscators for point programs have been shown.  ...  VBB, IND and BP Obfuscation We first recall the virtual black box definition and two of its previous relaxations. Definition 2.1 (obfuscator [3] ).  ... 
doi:10.1007/978-3-642-14623-7_28 fatcat:r4i4dcrshjf3nlfq2jwwvqpnua

Constant-Round Concurrent Zero-Knowledge from Indistinguishability Obfuscation [chapter]

Kai-Min Chung, Huijia Lin, Rafael Pass
2015 Lecture Notes in Computer Science  
Our protocol relies on the existence of families of collision-resistant hash functions, one-way permutations, and indistinguishability obfuscators for P/poly (with slightly super-polynomial security).  ...  The construction of [KLW14] makes use of an IO for P/poly, injective PRG, (selectively secure) puncturable PRF, and an IND-CPA secure public key encryption scheme.  ...  Assume the existence of indistinguishability obfuscation for P/poly (with slightly superpolynomial security), one-way permutations (with slightly super-polynomial security) and collisionresistant hash  ... 
doi:10.1007/978-3-662-47989-6_14 fatcat:xhb6miv2nvamje3yh5infuaxgi
« Previous Showing results 1 — 15 out of 66 results